A crystal system is a category of space groups, which characterize symmetry of structures in three dimensions with translational symmetry in three directions, having a discrete symmetry group. A major application is in crystallography, to categorize crystals, but by itself the topic is one of 3D Euclidean geometry. There are 7 crystal systems: Triclinic, all cases not satisfying the requirements of any other system; thus there is no other symmetry than translational symmetry, or the only extra kind is inversion.Including:

Crystal system - Crystallographic point group Crystal system - Overview of point groups by crystal system Crystal system - Classification of lattices

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Crystal system, Crystal system - Crystallographic point group, Crystal system - Overview of point groups by crystal system, Crystal system - Classification of lattices

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A symmetry group consists of isometric affine transformations; each is given by an orthogonal matrix and a translation vector (which may be the zero vector). Space groups can be grouped by the matrices involved, i.e. ignoring the translation vectors (see also Euclidean group). This corresponds to discrete symmetry groups with a fixed point. There are infinitely many of these point groups in three dimensions. However, only part of these are compatible with translational symmetry: the crystallographic point groups. This is expressed in the crystallographic restriction theorem. (In spite of these n ...

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Crystal system, Crystal system - Crystallographic point group, Crystal system - Overview of point groups by crystal system, Crystal system - Classification of lattices

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In crystallography, the cubic crystal system (or isometric crystal system) is the most symmetric of the 7 crystal systems. The system is composed of the three Bravais lattices whose symmetry group is that of a cube. The three Bravais lattices that form the cubic crystal system are: The cubes drawn are the conventional unit cells. For a cube whose vertices include 000 and 200, bcc has additional lattice point 111, while fcc has 110, 101, and 011. For bcc the primitive cells have a volume of 1/2 of the cube, e.g. th ...

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Cubic crystal system - Halite structure

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In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. A crystal structure is composed of a unit cell, a set of atoms arranged in a particular way; which is periodically repeated in three dimensions on a lattice. The spacing between unit cells in various directions are called its lattice parameters. The symmetry properties of the crystal are embodied in its space group. A crystal's structure and symmetry play a role in determining many of its properties, such as cleavage, el ...

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Crystal structure - Unit cell Crystal structure - Crystal system Crystal structure - Classification of lattices Crystal structure - Point and space groups Crystal structure - Defects in crystals Crystal structure - Crystal symmetry

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Sodium chloride forms fcc crystals. In these, the larger chloride ions are arranged in a cubic close-packing, while the smaller sodium ions fill the octahedral gaps between them. Each ion is surrounded by six of the other kind. This same basic structure is found in many other minerals, and is known as the halite structure. The sodium ions indicated in blue show that the fcc lattice can also be represented by mid-edge and centered lattice po ...

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Cubic crystal system, Cubic crystal system - Halite structure

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The principle of Varnasrama Dharma is one of the basic principles of Hinduism. The Varnasrama system is peculiar to Hindus. It is a characteristic feature of Hinduism. It is also prevalent throughout the world according to Guna-Karma (aptitude and conduct), though there is no such distinct denomination of this kind, elsewhere.

Excerpt from All About Hinduism by Sri Swami Sivananda

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The crystallographic point group or crystal class is the set of non-translational symmetries that leave a point in the crystal fixed. There are 32 possible crystal classes. The space group of the crystal structure is composed of the translational symmetries in addition to the symmetries of the point group. There are 230 distinct space groups. ...

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Crystal structure, Crystal structure - Unit cell, Crystal structure - Crystal system, Crystal structure - Classification of lattices, Crystal structure - Point and space groups, Crystal structure - Defects in crystals, Crystal structure - Crystal symmetry

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Crystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals. Crystallographers classify twinned crystals by a number of twin laws. These twin laws are specific to the crystal system. The type of twinn ...

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Crystal twinning - Reference

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Arsenopyrite is an iron arsenic sulfide (FeAsS). It is a hard (Moh's 5.5-6) metallic, opaque, steel grey to silver white mineral with a relatively high specific gravity of 6.1. When dissolved in nitric acid, it produces sulfur. When arsenopyrite is heated, it becomes magnetic, and gives off toxic fumes. Arsenopyrite contains about 46% arsenic and is a principle ore of arsenic. Arsenopyrite crystallizes in the monoclinic crystal system and often shows prismatic crystal or columnar forms with striations and twinning common. Arsenopyrite ...

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Crystal power is a belief that crystals have healing, mystical and paranormal powers. It is popular in the New Age movement, but regarded as baseless by skeptics and the general scientific community. Crystal power - Crystal healing. Crystal healers claim that every living organism has a "vibrational energy system," which includes chakras, subtle bodies and meridians. By using the appropriate crystals one can allegedly "tune" an energy system or rebalance energies, thus improving well-being. T ...

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Crystal power - Crystal healing
Crystal power - Criticism

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Cubic can mean several things: cubic function cubic equation cubic curve cubic graph cubic (crystal system) cube cubicle Other related archivescube, cubic (crystal system), cubic curve, cubic equation, cubic function, cubic graph, cubicle

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Crystal Mines is a video game that was released for the Nintendo Entertainment System by Color Dreams in 1989. Like all Color Dreams games, Crystal Mines was not officially licensed by Nintendo. According to the game's instruction manual, the player controls a robot via remote control to conduct a mining operation on a newly discovered planet in the year 2265. The robot can use energy balls to dig through dirt and rock as well as defeat enemies. On each level, the player is required to collect a certain number of crystals while ...

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Crystal Mines - Sources Crystal Mines - External Link

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Alunite, or alumstone, is a mineral that was first observed in the 15th century at Tolfa, near Rome, where it was mined for the manufacture of alum. First called aluminilite by JC Delametherie in 1707, this name was contracted by FS Beudant in 1824 to alunite. Distinct crystals of alunite are rarely found in cavities in the massive material. Alunite crystallizes in the hexagonal system with crystals forming trigonal pyramids that resemble rhombohedra with interfacial angles of 90 50', so that they resemble cubes in appearance. ...

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Riebeckite is a sodium-rich member of the amphibole group of minerals, chemical formula Na2(Fe,Mg)5Si8O22(OH)2. It crystallizes in the monoclinic system, usually as long prismatic crystals showing a diamond-shaped cross section, but also in fibrous, bladed, acicular, columnar, and radiating forms. Its hardness 5.0 - 6.0, and its specific gravity is 3.0 - 3.4. Cleavage is perfect, two directions in the shape of a diamond; fracture is uneven, splintery. It is often translucent to nearly opaque. It typically forms dark-blue elongated to fibrous crystals in highly sodic ...

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Chalcopyrite is a copper iron sulfide mineral that crystallizes in the tetragonal system. It has the chemical composition CuFeS2. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Due to its color and high copper content, chalcopyrite has often been referred to as "yellow copper". Chalcopyrite is often confused with pyrite, although the latter has a cubic and not a tetragonal crystal system. Further, chalcopyrite is more often massive and less brit ...

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Malachite is a carbonate mineral, copper(II) carbonate hydroxide Cu2CO3(OH)2. Malachite has a hardness between 3.5 and 4. It crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses. Malachite often results from weathering of copper ores and is often found together with azurite (Cu3(CO3)2(OH)2), goethite, and calcite. Except for the iridescent green colour, the properties of malachite are very simil ...

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Rhodonite is a member of the pyroxene group of minerals, consisting of manganese inosilicate, (Mn,Fe,Mg,Ca)SiO3, and crystallizing in the triclinic system. It commonly occurs as cleavable to compact masses with a rose-red color, often tending to brown because of surface oxidation. Rhodonite crystals often have a thick tabular habit, but are rare. It has a perfect, prismatic cleavage, almost at right angles. The hardness is 5.5 - 6.5, and the specific gravity 3.4 - 3.7; luster is vitreous, being less frequently pearly ...

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The tourmaline mineral group is chemically one of the most complicated groups of silicate minerals. It is a complex silicate of aluminium and boron, but because of isomorphous replacement (solid solution), its composition varies widely with sodium, calcium, iron, magnesium, lithium and other elements entering into the structure. Tourmaline belongs to the trigonal crystal system and occurs as long, slender to thick prismatic and columnar crystals that are usually triangular in cross-section. Interestingly, the style of terminati ...

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The mineral topaz is a silicate of aluminium and fluorine with the chemical formula Al2SiO4(F,OH)2. It crystallizes in the orthorhombic system and its crystals are mostly prismatic terminated by pyramidal and other faces, the basal pinacoid often being present. It has an easy and perfect basal cleavage and so gemstones or other fine specimens should be handled with care to avoid developing cleavage flaws. The fracture is conchoidal to uneven. Topaz has a hardness of 8, a specific gravity of 3.4-3.6, an ...

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